1. Field of the Invention
The present invention relates to a tiedown device for securing a wheel of a vehicle carried on a trailer or like conveyance.
2. Description of the Prior Art
Tiedown devices for securing a vehicle by its wheels on a trailer have been the subject of prior art patents. Generally, most vehicles being conveyed are automobiles or small trucks, and have pneumatic tires of dimensions conforming to a plurality of standard sizes. These standard sizes fall within a range of sizes corresponding to the great majority of privately owned vehicles.
Vehicles are transported for a variety of reasons, principally conveyance to a service facility following disablement. Other purposes include marine transport, as on a barge or ferry. All such carriers, wherein the vehicle is supported on a generally flat, horizontal surface, and secured thereto, will be referred to as conveyances. Although discussion herein refers to trailers, the principles presented will be understood to apply to all conveyances.
Specialized trailers and related equipment have been developed in order to provide economical and convenient trailering services to the motoring public.
An example of a strap type tiedown device is seen in U.S. Pat. No. 4,960,353, issued to Robert J. Thorndyke on Oct. 2, 1990 A basket is formed by straps wherein a first strap wraps circumferentially halfway around a vehicle tire, and a lateral connecting strap lies generally diametrically across both sides of the tire. The lateral connecting strap is sewed or otherwise attached to the circumferential strap where the two intersect on the tire tread. There are two such intersections, spaced roughly one hundred eighty degrees apart about the tire circumference.
The diameter of the basket is adjusted by tightening the circumferential member, and then by securing the lateral member by a buckle. This lateral member is not a continuous loop, and is rendered so by the buckle. In summary, the tiedown device of Thorndyke is secured by first tightening one member by pulling, and then manually connecting and tightening a buckle.
A vehicle tiedown system disclosed in U.S. Pat. No. 4,786,223, issued to Charles F. Crissy et al. on Nov. 22, 1988, also includes a basket arrangement partially encircling a tire. Apart from flexure of the flexible straps, there is no adjustment for different tire sizes. The basket arrangement of retaining straps comprises three bands, spaced apart approximately ninety degrees from one to the next. Each band extends from the side of the tire at the rotational axis around the tire to the rotational axis on the opposite side. All three such bands intersect at one point on each side of the tire.
U.S. Pat. Nos. 1,937,769 and 2,055,829, issued respectively to Carl Lute on Dec. 5, 1933, and to Kenneth J. Tobin on Sep. 29, 1936, disclose chain link tiedown devices. The device of Tobin '829 has a circumferential member which divides into two members, each extending concentrically on one side of the tire, then converging to form a unitary continuation of the circumferential member. This arrangement provides one forward tethered member secured to the trailer and one rear tethered member. A basket is formed by plural radially disposed chain segments connecting each concentric member to its counterpart. Each radial segment is formed in two parts which are mutually connected by hook and eye assemblies.
Assembly of the Tobin device therefore requires anchoring fore and aft by hooks, then manually connecting one hook and eye assembly for each radial segment provided. The device of Lute '769 is essentially similar, but no adjustment of the radial segments is provided.
European Patent Office Document No. 0,311,543, dated Dec. 4, 1989, discloses a strap type tiedown device comprising only a circumferential member.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.